I have been through most of this thread, and some stuff on Dean Roddy's site and Peat's as well. It intrigues me a bit since I think that thyroid might be the 1 thing that isn't working fantastically for me on Primal/PHD. The idea that supplanting starch with fructose might better support the thyroid seems worth a bit of investigation.

I have to say, though, it really doesn't pass the 'sniff test' for me, and the last few posts are a succinct start on why - the big 'epiphany' for me with Primal was seeing an extremely elegant description of how human metabolism worked, shaped by evolution. The fact that we can store only a very minimal amount of carbs but a great amount of fat seems to point clearly to an expectation that we'd run off fat as the base of our metabolism - the only other rational conclusion is that carbs were ubiquitously available and meal timing/frequency were entirely predictable; this seems absurd on it's face. If metabolizing stored fat were 'stressful' to the point of compromising health, one has to think that an adaptation towards higher glycogen storage would have become dominant. Or, equivalently, an alternate fat metabolic pathway that is less stressful would have been selected.

This type of argument doesn't 'prove' anything, but certainly makes it extremely difficult to accept something like 'burning fat is stressful' without substantial supporting evidence.

07-12-2012, 09:55 AM

yodiewan

[QUOTE=dwkdnvr;898097]I have been through most of this thread, and some stuff on Dean Roddy's site and Peat's as well. It intrigues me a bit since I think that thyroid might be the 1 thing that isn't working fantastically for me on Primal/PHD. The idea that supplanting starch with fructose might better support the thyroid seems worth a bit of investigation.

I have to say, though, it really doesn't pass the 'sniff test' for me, and the last few posts are a succinct start on why - the big 'epiphany' for me with Primal was seeing an extremely elegant description of how human metabolism worked, shaped by evolution. The fact that we can store only a very minimal amount of carbs but a great amount of fat seems to point clearly to an expectation that we'd run off fat as the base of our metabolism - the only other rational conclusion is that carbs were ubiquitously available and meal timing/frequency were entirely predictable; this seems absurd on it's face. If metabolizing stored fat were 'stressful' to the point of compromising health, one has to think that an adaptation towards higher glycogen storage would have become dominant. Or, equivalently, an alternate fat metabolic pathway that is less stressful would have been selected.

This type of argument doesn't 'prove' anything, but certainly makes it extremely difficult to accept something like 'burning fat is stressful' without substantial supporting evidence.[/QUOTE]

Very well said. Very good points and extremely logical.

07-12-2012, 10:29 AM

YogaBare

[QUOTE=dwkdnvr;898097]the big 'epiphany' for me with Primal was seeing an extremely elegant description of how human metabolism worked, shaped by evolution. The fact that we can store only a very minimal amount of carbs but a great amount of fat seems to point clearly to an expectation that we'd run off fat as the base of our metabolism - the only other rational conclusion is that carbs were ubiquitously available and meal timing/frequency were entirely predictable; this seems absurd on it's face. If metabolizing stored fat were 'stressful' to the point of compromising health, one has to think that an adaptation towards higher glycogen storage would have become dominant. Or, equivalently, an alternate fat metabolic pathway that is less stressful would have been selected.

This type of argument doesn't 'prove' anything, but certainly makes it extremely difficult to accept something like 'burning fat is stressful' without substantial supporting evidence.[/QUOTE]

Beautifully said. And I agree with you. I imagine people would have gorged on fruit in the summers, and stored it all as fat which enabled them to survive the winters when food was scarce. It's called hibernation... and most mammals do it ;)

What I've taken from all these posts with Danny is not to be too extreme with Primal. I was fearing sugars, but the science would indicate moderate amounts are beneficial. I'm not advocating the OJ / table sugar suggestions - though I imagine it works for some people. For me, a little fruit / honey / dark chocolate would prob be enough to keep everything in balance.

07-12-2012, 11:16 AM

SeanBissell

[QUOTE=YogaBare;898146]Beautifully said. And I agree with you. I imagine people would have gorged on fruit in the summers, and stored it all as fat which enabled them to survive the winters when food was scarce. It's called hibernation... and most mammals do it ;)

What I've taken from all these posts with Danny is not to be too extreme with Primal. I was fearing sugars, but the science would indicate moderate amounts are beneficial. I'm not advocating the OJ / table sugar suggestions - though I imagine it works for some people. For me, a little fruit / honey / dark chocolate would prob be enough to keep everything in balance.[/QUOTE]

I just gotta say...

You need water and air too, but you don't store much of those substances...

Not sure if storage equates to importance from a metabolic standpoint.
-Sean

07-12-2012, 11:19 AM

YogaBare

[QUOTE=SeanBissell;898192]You need water and air too, but you don't store much of those substances...[/QUOTE]

Are you for real? Our body is something like 60% water!! Our brains are 70%. I think that qualifies as teeny amount of storage.

07-12-2012, 11:27 AM

Neckhammer

[QUOTE=YogaBare;898195]Are you for real? Our body is something like 60% water!! Our brains are 70%. I think that qualifies as teeny amount of storage.[/QUOTE]

Yeah....I think we have some water stored. And some air for that matter, but if you would like to continue with this ridiculous analogy please expand on your thoughts Sean. Should be fun :)

07-12-2012, 11:44 AM

SeanBissell

[QUOTE=Neckhammer;898200]Yeah....I think we have some water stored. And some air for that matter, but if you would like to continue with this ridiculous analogy please expand on your thoughts Sean. Should be fun :)[/QUOTE]

In terms of "operating time" there's not much water or air stored to be used in metabolic processes.

How much time will you live if you don't take in any oxygen?

How much time will you live if you don't take in any water?

That's what I'm getting at.

07-12-2012, 11:49 AM

dwkdnvr

[QUOTE=SeanBissell;898192]I just gotta say...

You need water and air too, but you don't store much of those substances...

Not sure if storage equates to importance from a metabolic standpoint.
-Sean[/QUOTE]

It's not a question of 'importance', it's a question of role/function.

To make the logic more explicit......

If burning fat is 'stressful' but burning sugar isn't, then that would imply that the body will preferentially burn sugar whenever it's available. Since our glycogen storage is limited, burning it for basal metabolic processes would result in it running out in less than a single day. From an evolutionary standpoint, this makes no sense because the *critical* role that glycogen plays is anaerobic metabolism - i.e. fueling high-intensity activity of a 'flight or fight' nature'. Fat CAN'T fulfill this role. One day without food would leave you glycogen depleted, which is exactly when you're going to need to tap into it to go hunt etc.

So, burning glycogen for basal metabolism would leave the typical individual drained of glycogen unless they could do the modern 'several meals' deal EVERY SINGLE DAY. You have little to no resilience in the face of food scarcity. Leaving yourself drained of glycogen and thus unable to hunt/flee etc is simply not a behavior that would survive evolution for very long.

Thus, the evolutionary viewpoint seems pretty unmistakable - fat is used for fueling basic metabolism since it's abundant and can carry an individual for a very long time in the face of food scarcity, and can do it while sparing glycogen for when it's truly needed.

Having said that, it's pretty clear that Peat and his followers have no interest in this type of evolutionary thought process - they're basing their behavior on observation. That's fine as far as it goes, and maybe chugging high levels of fructose in the absence of PUFA does exploit some otherwise unknown loophole in our metabolic process. It's possible, but my perspective is that we have a rather poor track record at that type of attempt to improve upon or circumvent 'mother nature', and I certainly would need to see a heck of a lot more evidence before considering it valid.

07-12-2012, 11:58 AM

SeanBissell

[QUOTE=dwkdnvr;898224]It's not a question of 'importance', it's a question of role/function.

To make the logic more explicit......

If burning fat is 'stressful' but burning sugar isn't, then that would imply that the body will preferentially burn sugar whenever it's available. Since our glycogen storage is limited, burning it for basal metabolic processes would result in it running out in less than a single day. From an evolutionary standpoint, this makes no sense because the *critical* role that glycogen plays is anaerobic metabolism - i.e. fueling high-intensity activity of a 'flight or fight' nature'. Fat CAN'T fulfill this role. One day without food would leave you glycogen depleted, which is exactly when you're going to need to tap into it to go hunt etc.

So, burning glycogen for basal metabolism would leave the typical individual drained of glycogen unless they could do the modern 'several meals' deal EVERY SINGLE DAY. You have little to no resilience in the face of food scarcity. Leaving yourself drained of glycogen and thus unable to hunt/flee etc is simply not a behavior that would survive evolution for very long.

Thus, the evolutionary viewpoint seems pretty unmistakable - fat is used for fueling basic metabolism since it's abundant and can carry an individual for a very long time in the face of food scarcity, and can do it while sparing glycogen for when it's truly needed.

Having said that, it's pretty clear that Peat and his followers have no interest in this type of evolutionary thought process - they're basing their behavior on observation. That's fine as far as it goes, and maybe chugging high levels of fructose in the absence of PUFA does exploit some otherwise unknown loophole in our metabolic process. It's possible, but my perspective is that we have a rather poor track record at that type of attempt to improve upon or circumvent 'mother nature', and I certainly would need to see a heck of a lot more evidence before considering it valid.[/QUOTE]

Great points for sure.

At the same time, I do think there's value in actually studying things on the cellular level rather than looking at how we think things evolved from a "common sense" level.

Because I've noticed that in nutrition "common sense" isn't always common :)

Regardless though. Even if we're supposed to use fat as a primary fuel, how come "leanness" is so valued and fat loss is such a large discussion?

07-12-2012, 12:10 PM

Neckhammer

[QUOTE=SeanBissell;898239]
Regardless though. Even if we're supposed to use fat as a primary fuel, how come "leanness" is so valued and fat loss is such a large discussion?[/QUOTE]

Great point! And one reason that I for one see no real value to hacking various forms of exercise or diet to achieve some preconceived (media driven) ideal level of leanness. As a male I sit in the 12-15% category for body fat and am quite happy with that. So what if you can't see the veins in my abs.....lol I didn't know you were suppose to!